The early detection of anomalous human tissue, and in particular the detection of undesirable tissue such as fat, fibrous tumors, or cancerous tissue is a much felt need. For example, recent findings indicate that one out of eight women will develop breast cancer, the second leading cause of death in women. The earliest indication of breast cancer generally is the occurrence of a painless lump, sometimes associated with nipple discharge and skin retraction. Unfortunately, later, more obvious and less survivable indications of cancer are generally due to metastases to bone, brain, lungs and liver. Accordingly, early detection of anomalus tissue and tissue changes is essential for improvement of survivability and effective treatment. Attempts at early detection through monthly self-examinations and mammography have proven beneficial but have not satisfied the need for more effective methods of early detection and corresponding treatment.
By way of example, if small lumps, less than 20 mm, can be detected early they can then be diagnosed by a biopsy and treated should the lump be found to be malignant. Accordingly, early detection allows for less invasive treatment, such as a lumpectomy with possible radiation treatment of axillary nodes making less likely the need for a modified radical mastectomy with axillary node dissection. In addition, through early treatment the five-year survival rate can be improved by as much as 85 percent. Absent early detection, distant metastasis can reduce survival rates to 10 percent or less. The present invention addresses this very critical need.
Although early detection is essential, it can be difficult to achieve even by skilled physicians. Monthly self-examinations are helpful, particularly when followed by the examination of a physician in the event a mass is self-detected. It is, however, difficult for an unskilled individual to do a thorough examination, and unlikely that very small lumps will be detected.
Presently, anomalies in tissue, particularly breast tissue, are detected mostly by periodic palpation by the hand of a physician or radiographic mammography. To be effective, however, hand palpation must be frequent, particularly in older women, to detect tumors before the tumors metastasize. Unfortunately, the subjective nature of hand palpation and the frequency required to make these examinations effective create limitations rendering hand palpation examinations ineffective due to inconvenience, availability, and cost In addition, mammography is troublesome due to the concern of accumulated radiation exposure from frequent mammograms. Furthermore, mammography, unlike palpation, can be limited because very small tumors are not detected, particularly in the denser breast tissue of younger women.
In addition to anomalies, it is also important that changes in tissue structure, and changes in tissue characteristics, be detected and monitored over time. The problem, therefore, is how to detect minor changes in tissue. For example, hand palpation of tissue may not reveal small characteristic changes or anomalies within breast tissue until the changes are so substantial, or the anomalies so prominent, that they are no longer responsive to early treatment.
Another problem limiting the effectiveness of hand palpation is the inability to record, retain, and at a later time recall, historical data of prior detected anomalies, including location and the nature of the changes over time. This is particularly the case for soft anomalous tissue located further from the surface of the skin, having diameters less than 10 mm. Also, anomalies deeper in the tissue of large breasts are particularly difficult to detect by hand palpation. Even if detected, it is often not possible to characterize the tissue or changes in the tissue due to the subjective nature and lack of standards for hand palpation, which almost entirely depends on the skill and sensitivity of the examining physician.
Accordingly, the present invention addresses each of the aforementioned problems and urgent needs. The present invention provides methods and systems for early detection of tissue anomalies and changes in tissue characteristics through color imaging of tissue characteristics, the color images displaying variations of predetermined tissue characteristics over selected regions of tissue to facilitate the accurate and early detection of tissue anomalies, even very small anomalies. The present invention also addresses the need to objectively determine tissue characteristics and produce, maintain, and compare images of these characteristics, over time, the images mapping selected regions of tissue to track characteristic changes over time.